The Catalan coach recorded a half-century against Everton on Saturday, in what was his 69th fixture at the helm.
Mourinho achieved the feat in 63 matches while in charge of Chelsea, so can claim to still have one over on an old adversary.
The 2017-18 campaign has, however, been all about the men from the blue half of Manchester.
A comfortable 3-1 victory over Everton has carried them ever close to title glory, with it possible that the crown could be wrapped up in their next league fixture – a derby date with Manchester United and Mourinho.
Guardiola will head into that game having lifted City to new heights, with every domestic rival having now been beaten across the course of a single season.
Only two sides – Chelsea in 2005-06 and United in 2010-11 – have done that before, with Everton the final piece of the jigsaw for City.
Guardiola can also claim to have seen off every Premier League rival he has faced since arriving in English football, with the Toffees picked off at the fourth time of asking.
Guardiola’s first Premier League game as City boss came against Sunderland on August 13, 2016.
He recorded a 2-1 victory that day and has savoured many more successes since.
City have won 27 of their 31 top-flight fixtures this season, with Liverpool the only side to have beaten them.
Having ended his debut campaign without a trophy for the first time in his distinguished coaching career, Guardiola is now on course for a treble.
The Carabao Cup has already been wrapped up and the Premier League title will follow shortly.
City are also through to the quarter-finals of the Champions League, where they will face Liverpool, and could see 2018 become an historic year as they taste European Cup glory for the first time.